A circuit board typically has conductive areas which terminate at a series of positions spaced along an edge of the board for connection through a socket with other circuits. The conductive areas may be on one or both faces of the circuit board and if on both may be connected together (single sided) or electrically independent (double sided). A zero insertion force socket has contacts spaced to receive the circuit board edge with little or no interference so long as the circuit board is inserted at an appropriate angle. After insertion, the board is moved angularly to engage the socket contacts and mechanically latched in engaged position. The socket is typically mounted on a carrier, as another circuit board or a chassis. Several different configurations are common. In a straight or upright socket the latched circuit board is at right angles to the carrier. In a right angle socket, the latched circuit board is parallel with the carrier. In a low profile socket the latched circuit board extends upwardly from the carrier at an angle of the order of 25.degree.. The length of the socket is determined by the number of circuits or conductive area positions on the board.
Circuit board sockets typically have a molded plastic housing in which the contacts are inserted following molding. Different molds are required for each style and size of socket. Contacts which have been used in the prior art have flexible sections subjected to high stress when flexed by rotation of the circuit board to the latched position. This results in contact breakage which requires replacement of the socket. Either the socket must be unsoldered, removed from the carrier and replaced or the entire carrier and the associated circuit elements replaced.
Examples of prior art ZIF sockets are found in Tighe 3,848,952, Then et al. 4,136,917, Regnier et al. 4,713,013 and Gardner 4,718,859.